Good (hasan)
graded by Al-Albani
Mishkat al-Masabih 636
عَن زيد بن ثَابت وَعَائِشَة قَالَا: الصَّلَاةُ الْوُسْطَى صَلَاةُ الظُّهْرِ رَوَاهُ مَالِكٌ عَن زيد وَالتِّرْمِذِيّ عَنْهُمَا تَعْلِيقا
Zaid b. Thabit and ‘A’isha said that the middle prayer is the noon prayer. Malik transmitted it from Zaid and Tirmidhi from both of them without a full isnad.
Cited in Mishkat al-Masabih (No. 636).